I've been seeing some cold riding threads, so I thought this might be a good time to post this link. Type in the temperature and speed and it calculates the wind chill. It calculates the old wind chill factor and the new wind chill factor. The old wind chill calculation posts a colder fahrenheit wind chill and a warmer celsius wind chill than the new calculation and the new wind chill calculation posts a warmer fahrenheit calculation and a colder celsius wind chill than the old calculation. Could be a formula error.